Incandescent lamp.



E. H. SMITH.

INUANDESUENT LAMP,

APPLICATION FILED AUG. 21, 1908,

Patented Aug. 24-, 19%.

E'Jvwanfoz Ziizmmi H Smith,

afloat:

Witmmu' UNITED STATES PATENT OFFICE.

Enwann n. snrrn, or ABERDEEN, FASHINGTON,'11SSIGNOB or Two-Tmnns 'ro'rnolus m'rcnnLn' ol ABERDEEN, WASHINGTON.

mcalvnnscnn'r LAMP.

Specification of Letters Patent.

Patented Aug. 24, 1909.

Application filed hugust 21, 1908. Serial No. 449,680.

To all whom it may concern:

Be it known that I, EDWARD H. SMITH, a citizen of the United States,residing at Aberdeen, in the county of Chehalis and State of Washin ton,have invented certain new and useful mprovements in Incandescent Lamps,of which the following is aspecification, reference being had therein tothe accompanying drawing.

This invention relates to incandescent electric lamps, and hasparticular reference to means for regulating the illuminating effect of.a lamp of this 'class. I

The primary object of the invention is to provide an incandescentelectric lamp with simple and effective exteriorly o erative means forcontrolling the glow of t e same and cause it to give forth a full lightin accordance withits candle power or only a partial light, or to outout and extinguish the lamp, and dispense entirely with the use of abutton ordinarily employed to turn on or oil a lamp of the typespecified.

The invention consists of the construction and arrangement which will bemore fully hereinafter specified. I

In the drawings :Figure I is a transverse section through anincandescent lamp em bodying the features of the invention. Fig.

II is a detail elevation of the screw plug portion of the lamp. Fig. IIIis'a detailelevation of the lamp head. -Fig. IV is a bottom lan view ofthe plug and head portion of the amp, the bulb being removed, and Fig. Vis a detail perspective'of a portion of the lamp.

The numeral (5) designates an incandescent lamp bulb havin threeleading-in wires (6), (7 and (8) whic are connected to two sets offilaments (9) and (10) supported within the bulb in the usual manner.tallic collar (11) surrounds and is secured to the head of the bulb (5)and thereover is fitted the flan e or rim (12) of a hollow head (13)inclosed y a screw plug member (14) havinga flange or Iim (15) embracinthe flange or rim (12). The head (13) and ange (12) are rotatable in themember (14) and flange (15) and the latter may be termed a seat and theformer contact means or an annular switch. The screw plug member (14) isprovided with a contact plate (16) to which the leading in wire (6) isconnected as shown by Fig. I, and on the flange or rim (12) of the head(13) are two contact points (17) and (18) which extend through to theinterior of the lam and have. the leading in wires (7) and (8respectively connected thereto. The flange or rim (12) is also providedwith suitably spaced studs (19) projecting outwardly from the exteriorsurface thereof to engage circumferential slots (20) in the flange orrim (15) of the socket member (14) so as to limit the rotation of thelamp bulb and head (13) in said member.

The flan e or rim (15) is formed with an outstruck iridge (21) having acentral instruck contact projection (22) to engage the exteriorlyexposed portions of the contacts (17) and (18), the projection (22)hearing closely against the outer surface of the flange or rim (13) toinsure reliable engagement of the said and (18).

The leading wire (6) is branched, as at 23, a part thereof connectinwith the filament (9) and apart with the ament (10). The wires (7) and(8) respectively connect with the opposite portions of filaments (10)and (9). The wire (6) may be termed the current feeding wire as itconnects with'the line or feeder from a source of electrical generationthrough the contact plate (16), and the circuits for the two filamentsboth include the wire (6).

From the-foregoin it will be seen that when the lamp bulb 1s turned tobring the projection (22) into engagement with the contact (18), thecircuit of the filament (9) is completed and the lampulwill glow to itsglow, or turned off entirely for extinguish:

in p

It be obvious from the foregoing description that the use of a contactmember a formed in the manner described insures of the necessaryresiliency to permit. the same I being snapped from the terminalcontact,

and, further, the flange or arm is not in any manner weakened by theformation of the contact thereon,'nor is there any waste of projectionwith the contacts (17) agem'ent with relation to' material, such as willincrease the cost of the same.

The im roved features hereinbefore specified may e a plied toincandescent lamps of varying cand e powers, and in view of thesimplicity of structure of the several parts the equipment of a lamptherewith may be accomplished at a minimum expense.

It should be understood that in its broader aspect the inventioncomprehends the em ployment not only of the various means described, butof equivalent means for performing the recited functions. While thearrangement shown is thou ht, at the present time, to be preferable, it1s desired to reserve the right to effect such modifications andvariations thereof as may come fairly within the scope of the appendedclaims.

What is claimed as new, is An incandescent lamp, comprising a plug 20provided with a flange having an indented ridging portion forming acontact, a bulb, a head therefor rotatably mounted in said plug, spacedapart contacts carried by said head, and means for limiting the movement25 of the head relative to the plug.

In testimony whereof I hereunto affix my signature in presence of twowitnesses.

EDWARD H. SMITH. Witnesses:

W. L. EGHOLS, JOHN OHARA;

